Diversity and Spatial Distribution of Molluscs along the Salinity Gradient in Ashtamudi Lake Ramsar Site, Kerala, India
Keywords:Ashtamudi, Salinity, Estuary, Gastropods, Bivalves, Diversity index
Study of the diversity and spatial distribution of molluscs along salinity gradient in Ashtamudi Lake recorded the presence of 83 species with one polyplacophoran, 41 gastropods, 37 bivalves and four cephalopods. The species diversity in various salinity zones was in the order: saline zone- 80 species > estuarine zone- 28 species > freshwater zone- 14 species. The report includes three species new to the west coast of India: Assiminea woodmasoniana G. Nevill, 1880, Rugalucina vietnamica (Zorina, 1978) and Platevindex martensi (Plate, 1893). Species: such as Chiton granoradiatus Leloup, 1937; Clithon sowerbianum (Récluz, 1843); Littoraria pallescens (Philippi, 1846); Acteocina decorata (Pilsbry, 1904); Alaona ala (Hanley, 1845) and Serratina siamensis (E. von Martens, 1860) are new to Kerala. The paper analyses the alpha and beta diversity of molluscs in the Ashtamudi Lake, Kerala.